We also considered the case of planets which are predominantly iron (blue lines in Fig. REF a–f): this produces the smallest conceivable planet radii for the measured masses. As discussed by [1]} iron planets may arise from collisionally-driven mantle stripping or formation from iron-enriched material, but as discussed in Section REF , we propose that mantle ablation is a key process in DMPP-1.
We used the pure iron planet models of [2]}
to derive the radii corresponding to the minimum masses of these planets (see Table REF ). We establish that if planets have been ablated down to iron cores, DMPP-1 c, d and d\(^{\prime }\)  are potentially detectable, but only over a reduced range of impact parameters (\(b<0.591,0.621\)  and \(0.531\)  respectively), while DMPP-1 e, e\(^{\prime }\)  and f\(^{\prime }\)  would be too small to produce detectable transits.
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